WIND TUNNEL INVESTIGATION OF THE MK 76 PRACTICE BOMB

The results are presented of the static and dynamic wind tunnel tests of the basic body with various combinations of fuzes, lugs and tails. Originally, the configuration consisted of the basic body with a shrouded cruciform tail. This bomb had an impact fuze and a carrying lug. The effect of the presence of this fuze and lug on the bombs normal force and pitching moment were investigated in the Mach number range between 0.29 and 1.75. The effect of moving the tail aft slightly was also investigated. The results of these tests indicated a center of pressure 3.2 calibers aft of the nose. Moving the tail aft brought the center of pressure aft to a point 3.8 calibers from the nose. It was then decided to replace the shrouded tail by two tails of unshrouded design. The first of these was a cruciform tail with a swept leading edge. The basic body was tested with this tail in three positions. The result was a center of pressure location 4.0 calibers aft of the nose, for the forward position of the tail. Finally, a cruciform tail of rectangular fins was tested. The result was a center of pressure location of about 4.6 calibers aft of the nose.